Hi Albert,
On Tue, Oct 20, 2015 at 09:05:32AM +0200, Albert ARIBAUD wrote:
Hello Peng,
On Tue, 20 Oct 2015 13:59:53 +0800, Peng Fan Peng.Fan@freescale.com wrote:
The code such as PSCI in section named secure is bundled with u-boot image, and when bootm, the code will be copied to their runtime address same to compliation/linking address - CONFIG_ARMV7_SECURE_BASE.
When compile the PSCI code and link it into the u-boot image, there will be relocation entries in .rel.dyn section for PSCI. Actually, we do not needs these relocation entries.
If still keep the relocation entries in .rel.dyn section, r0 at line 103 and 106 in arch/arm/lib/relocate.S may be an invalid address which may not support read/write for one SoC. 102 /* relative fix: increase location by offset */ 103 add r0, r0, r4 104 ldr r1, [r0] 105 add r1, r1, r4 106 str r1, [r0]
So discard the relocation entries for code in secure section.
Actually, I'll need you to do a slight change -- that's my fault, and karma even ensured that my own self of two years ago would be the one to come and kick me. See:
http://lists.denx.de/pipermail/u-boot/2013-December/168652.html
Ok. Then arch/arm/cpu/armv8/u-boot.lds should also have such fix, since lots sections are discarded in u-boot.lds for armv8.
Which basically is about never discarding any section in the ELF file, and only copying a subset of the ELF sections into the binary file.
So rather than discarding the secure relocation records, let's move them to another section as you had proposed, and thus change the line
- /DISCARD/ : { *(.rel._secure*) }
Into a
.rel._secure { *(.rel._secure*) }
Placed right after the already present
.dynamic : { *(.dynamic*) }
It can not be placed after .dynamic, since the following is at front. 87 .rel.dyn : { 88 *(.rel*) 89 } So relocation entry from secure text will first placed into .rel.dyn section.
If not DISCARD, then I prefer to put ".rel.secure : { *(.rel._secure*) }" at line 55 which is wrapped by CONFIG_ARMV7_NONSEC in arch/arm/cpu/u-boot.lds.
See following patch:
From 4b950418835ff52cd7be8dd2b80fb8b0e055f9a2 Mon Sep 17 00:00:00 2001
From: Peng Fan Peng.Fan@freescale.com Date: Tue, 20 Oct 2015 15:18:22 +0800 Subject: [PATCH] arm: move relocation entry for secure section into a single section
The code such as PSCI in section named secure is bundled with u-boot image, and when bootm, the code will be copied to their runtime address same to compliation/linking address - CONFIG_ARMV7_SECURE_BASE.
When compile the PSCI code and link it into the u-boot image, there will be relocation entries in .rel.dyn section for PSCI. Actually, we do not needs these relocation entries.
If still keep the relocation entries in .rel.dyn section, r0 at line 103 and 106 in arch/arm/lib/relocate.S may be an invalid address which may not support read/write for one SoC. 102 /* relative fix: increase location by offset */ 103 add r0, r0, r4 104 ldr r1, [r0] 105 add r1, r1, r4 106 str r1, [r0]
So move them into a single section to avoid touching the relocation entry in arch/arm/lib/relocate.S.
Signed-off-by: Peng Fan Peng.Fan@freescale.com Cc: Tom Warren twarren@nvidia.com Cc: York Sun yorksun@freescale.com Cc: Hans De Goede hdegoede@redhat.com Cc: Ian Campbell ijc@hellion.org.uk Cc: Albert Aribaud albert.u.boot@aribaud.net Cc: Tom Rini trini@konsulko.com Cc: Jan Kiszka jan.kiszka@siemens.com Cc: Stefano Babic sbabic@denx.de --- arch/arm/cpu/u-boot.lds | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/arch/arm/cpu/u-boot.lds b/arch/arm/cpu/u-boot.lds index 03cd9f6..65986e8 100644 --- a/arch/arm/cpu/u-boot.lds +++ b/arch/arm/cpu/u-boot.lds @@ -51,6 +51,8 @@ SECTIONS *(.__secure_end) LONG(0x1d1071c); /* Must output something to reset LMA */ } + + .rel.secure : { *(.rel._secure*) } #endif
. = ALIGN(4);
Regards, Peng.
With my apologies for the very late realization.
Amicalement,
Albert.
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